From ZmnSCPxj at protonmail.com  Thu Sep  1 02:55:21 2022
From: ZmnSCPxj at protonmail.com (ZmnSCPxj)
Date: Thu, 01 Sep 2022 02:55:21 +0000
Subject: [Lightning-dev] Supporting a custodial user who wishes to
	withdraw all sats from the account...
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Good morning Martin,

> Hi folks,
> 
> I think I've seen wallets supporting "send max" when a zero-amount invoice was used. So isn't it a problem with the custodial service not supporting it?
> Whatever idea we figure out they can just refuse to implement it so we can't force them into improving and being custodial they could steal already, so that shouldn't be an issue.

Indeed, this is the simplest solution.
And as you point out, they could steal the whole funds outright anyway, and similarly they can always pretend that the actual routing fees paid were higher than they actually were.

Regards,
ZmnSCPxj